A Guanidinobenzol-Rich Polymer Overcoming Cascade Delivery Barriers for CRISPR-Cas9 Genome Editing.

The efficient cytosolic delivery of the CRISPR-Cas9 machinery remains a challenge for genome editing. Herein, we performed ligand screening and identified a guanidinobenzol-rich polymer to overcome the cascade delivery barriers of CRISPR-Cas9 ribonucleoproteins (RNPs) for genome editing. RNPs were stably loaded into the polymeric nanoparticles (PGBA NPs) by their inherent affinity. The polymer facilitated rapid endosomal escape of RNPs via a dynamic multiple-step cascade process. Importantly, the incorporation of fluorescence in the polymer helps to identify the correlation between cellular uptake and editing efficiency, increasing the efficiency up to 70% from the initial 30% for the enrichment of edited cells. The PGBA NPs efficiently deliver RNPs for in vivo gene editing via both local and systemic injections and dramatically reduce PCSK9 level. These results indicate that PGBA NPs enable the cascade delivery of RNPs for genome editing, showing great promise in broadening the therapeutic potential of the CRISPR-Cas9 technique.

Long-term haplodeficency of DSPP causes temporomandibular joint osteoarthritis in mice.

BACKGROUND: Extracellular matrix (ECM) protein malfunction or defect may lead to temporomandibular joint osteoarthritis (TMJ OA). Dentin sialophophoprotein (DSPP) is a mandibular condylar cartilage ECM protein, and its deletion impacted cell proliferation and other extracellular matrix alterations of postnatal condylar cartilage. However, it remains unclear if long-term loss of function of DSPP leads to TMJ OA. The study aimed to test the hypothesis that long-term haploinsufficiency of DSPP causes TMJ OA. MATERIALS AND METHODS: To determine whether Dspp+/- mice exhibit TMJ OA but no severe tooth defects, mandibles of wild-type (WT), Dspp+/-, and Dspp homozygous (Dspp-/-) mice were analyzed by Micro-computed tomography (micro-CT). To characterize the progression and possible mechanisms of osteoarthritic degeneration over time in Dspp+/- mice over time, condyles of Dspp+/- and WT mice were analyzed radiologically, histologically, and immunohistochemically. RESULTS: Micro-CT and histomorphometric analyses revealed that Dspp+/- and Dspp-/- mice had significantly lower subchondral bone mass, bone volume fraction, bone mineral density, and trabecular thickness compared to WT mice at 12 months. Interestingly, in contrast to Dspp-/- mice which exhibited tooth loss, Dspp+/- mice had minor tooth defects. RNA sequencing data showed that haplodeficency of DSPP affects the biological process of ossification and osteoclast differentiation. Additionally, histological analysis showed that Dspp+/- mice had condylar cartilage fissures, reduced cartilage thickness, decreased articular cell numbers and severe subchondral bone cavities, and with signs that were exaggerated with age. Radiographic data showed an increase in subchondral osteoporosis up to 18 months and osteophyte formation at 21 months. Moreover, Dspp+/- mice showed increased distribution of osteoclasts in the subchondral bone and increased expression of MMP2, IL-6, FN-1, and TLR4 in the mandibular condylar cartilage. CONCLUSIONS: Dspp+/- mice exhibit TMJ OA in a time-dependent manner, with lesions in the mandibular condyle attributed to hypomineralization of subchondral bone and breakdown of the mandibular condylar cartilage, accompanied by upregulation of inflammatory markers.

Expansion Technique for Reconstruction of Craniofacial Defect after Plexiform Neurofibroma Excision.

Reconstruction of large craniofacial defect after plexiform neurofibroma excision poses a continuous challenge for plastic surgeons, on account of characteristics of plexiform neurofibroma and patients' aesthetic requirements. Skin graft or free flap is hard to obtain satisfactory results or may pose technical challenges. In an attempt to provide the coverage with 'like tissue', we chose local tissue expansion technique. The expansion period was about an average of 3.4 months. We performed 19 expanded flaps located in the head, face, neck, forearm and superclavical regions to reconstruct the craniofacial defect and achieved satisfactory results. Preoperative endovascular embolism in some cases and several intraoperative hemostatic methods for all cases were undertaken to control the perioperative bleeding. For patients who request aesthetic results and are allowed two-staged operations, our method is viable.

Buccal Myomucosal Flap for Reconstruction of Red Lip Defects Close to Mouth Angle.

BACKGROUND: Owing to the special esthetic and functional role in the face, red lip reconstruction presents a challenge to plastic surgeons. Various reconstructive techniques can be employed to fix the red lip defects close to the mouth angle. The purpose of this study was to demonstrate that the buccal myomucosal flap could be an available option to repair red lip defects with preservation of its esthetics and function. METHODS: A single-center, retrospective study of 7 patients with red lip defects who were treated with buccal myomucosal flap was conducted between June 2017 and March 2022. All patients were followed up for at least 6 months including questionnaires and photography. RESULTS: Of these 7 patients, 2 were women, and 5 were men. The average age was 14.3 years (range, 1-32 y). All the buccal myomucosal flaps survived well. All the donor sites were closed directly without complications. The average follow-up time was 33.4 months (range, 6-57 mo). All patients were satisfied with the aesthetic and functional results. CONCLUSION: The buccal myomucosal flap is versatile and reliable, with the advantages of rich vascularity, flexible design, and easy access. This study was presented to highlight that the flap could be a good candidate to treat red lip defects close to the mouth angle.

In Vivo Imaging of Exosomes Labeled with NIR-II Polymer Dots in Liver-Injured Mice.

Mesenchymal stem cell-derived exosomes (MSC-Exos) are emerging as a promising platform for treating various intractable diseases and organ injuries. Monitoring their migration, homing, and therapeutic capability in vivo is essential to develop exosome-based theranostics. Here, we designed fluorescent semiconductor polymer dots (Pdots) in the second near-infrared window (NIR-II) for bright labeling and tracking of MSC-Exos. Glucose-coated Pdots (Pdots-Glu) were able to label MSC-Exos without changing their biological properties. The NIR-II fluorescent Pdots allow for high labeling brightness and long-term in vivo tracking of MSC-Exos. We investigated the biodistributions and therapeutic functions of these labeled MSC-Exos in liver-resected mice. In vivo and ex vivo imaging demonstrated that the Pdot-labeled MSC-Exos injected via the tail vein mainly accumulated in the residual liver tissue. In terms of the therapeutic effect, MSC-Exos may accelerate postoperative liver function recovery by inhibiting inflammatory responses, promoting cell proliferation, and resisting apoptosis. Our results indicated that MSC-Exos therapeutic systems hold promising applications in liver regenerative medicine.

Chemiluminescence sensors based on molecularly imprinted polymers for the determination of organophosphorus in milk.

As a food adapted to all kinds of people, milk has a high nutritional value. Because milk is a complex biological matrix, detecting illegal compounds is often difficult. As a common pesticide, organophosphorus (OP) residues caused by nonstandard use may be ignored, which is a threat to milk quality. In this study, using coumaphos as template molecule, the synthesized molecularly imprinted polymer (MIP) can specifically recognize 7 kinds of OP. Then, the MIP was used as an identification element to prepare a chemiluminescence sensor on a 96-well microplate for the determination of OP residues in milk samples. Due to the 4-(imidazol-1-yl)phenol-enhanced luminol-H2O2 system, the sensitivity of the system is very high; the detection limits of 7 OP including coumaphos, fenthion, chlorpyrifos, parathion, diazinon, fenchlorphos, and fenitrothion were 1 to 3 pg/mL, and the half maximal inhibitory concentrations were 1 to 20 ng/mL. The intraday recoveries of 7 OP were in the range of 86.1 to 86.5%, and the interday recoveries were in the range of 83.6 to 94.2%. Furthermore, the sensor can be reused up to 5 times. Therefore, the MIP-based chemiluminescence sensor can be used as a routine tool to detect OP residues in milk samples.

Facial and Neck Reconstruction With Pre-expanded Medial Upper Arm Flap: An Alternative method and 20-Year Experience.

PURPOSE: To present our experience with pre-expanded medial upper arm flap in facial and neck reconstruction. PATIENTS AND METHODS: This was a retrospective study operated between January 1st, 2001 and January 1st, 2021, at the Plastic Surgery Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College. Staged face and/or neck reconstruction was performed. RESULTS: Forty-one patients were treated in our institution and thirty-eight patients (forty-three flaps) were included in this cohort as. They ranged from 6 to 44 years old. There was no total flap loss in the cohort. Partial flap necrosis was observed in the earlier patients (4 cases). CONCLUSION: Pre-expanded medial upper arm flap is well matched to the facial and neck skin in color, texture, and thickness. Considering the excellent aesthetic outcomes, this flap is a good alternative for selected patients with soft tissue defects of the head and neck.

Measuring Cellular Uptake of Polymer Dots for Quantitative Imaging and Photodynamic Therapy.

There is a great deal of interest in the development of nanoparticles for biomedicine. The question of how many nanoparticles are taken up by cells is important for biomedical applications. Here, we describe a fluorescence method for the quantitative measurement of the cellular uptake of polymer dots (Pdots) and a further estimation of intracellular Pdots photosensitizer for fluorescence imaging and photodynamic therapy. The approach relies on the high brightness, excellent stability, minimal aggregation quenching, and metalloporphyrin doping properties of the Pdots. We correlated the single-cell fluorescence brightness obtained from fluorescence spectrometry, confocal microscopy, and flow cytometry with the number of endocytosed Pdots, which was validated by inductively coupled plasma mass spectrometry. Our results indicated that, on average, ∼1.3 million Pdots were taken up by single cells that were incubated for 4 h with arginine 8-Pdots (40 µg/mL, ∼20 nm diameter). The absolute number of endocytosed Pdots of individual cells could be estimated from confocal microscopy by comparing the single-cell brightness with the average intensity. Furthermore, we investigated the cell viability as a result of an intracellular Pdots photosensitizer, from which the half maximal inhibitory concentration was determined to be ∼7.2 × 105 Pdots per cell under the light dose of 60 J/cm2. This study provides an effective method for quantifying endocytosed Pdots, which can be extended to investigate the cellular uptake of various conjugated polymer carriers in biomedicine.

Urchin-like Hydroxyapatite/Graphene Hollow Microspheres as pH-Responsive Bone Drug Carriers.

Hydroxyapatite (HA) is the main inorganic component of human bones and teeth. It has good biocompatibility and bioactivity, which promotes its good application prospects in the field of bone drug carriers. In this study, tetraethylenepentamine-graphene (rGO-TEPA)/CaCO3:HA composite microspheres were prepared via microwave hydrothermal synthesis using rGO-TEPA/CaCO3 solid microspheres as intermediates. Furthermore, the incompletely transformed CaCO3 was removed by soaking in a citric acid buffer to obtain rGO-TEPA/HA hollow composite microspheres. The two types of as-prepared composite microspheres exhibited sea urchin-like structures, large BET surface areas, and good dispersibility. Mouse preosteoblast cells (MC3T3-E1) were used for in vitro cytotoxicity experiments. The in vitro cell viability test showed that the two composite drug carriers exhibited noncytotoxicity. Moreover, the doxorubicin (DOX) loading and releasing investigations revealed that the two types of prepared carriers had mild storage-release behaviors and good pH responsiveness. Hence, these rGO-TEPA/HA hollow microspheres have promising applications as bone drug carriers.

Facial Animation With Free Functional Gracilis Transfer Innervated by the Cross-Facial Nerve Graft.

BACKGROUND: The treatment of long-standing facial paralysis has always been a challenge for plastic surgery. The purpose of this study was to demonstrate that the free functional gracilis transfer innervated by the cross-facial nerve graft (CFNG) is still an ideal option, even though there are many new surgical options available. METHODS: A retrospective survey was made on 12 patients who received free functional gracilis transfer innervated by the CFNG. A modified version of the House-Brackmann scale was used to evaluate the movement of the corners of mouth after surgery. Patients were also asked about their satisfaction with the operation. In addition, an objective test was performed to assess the postoperative angle improvement by measuring the angle formed between the horizontal line of both corners of the lips and the vertical midline. RESULTS: All grafts survived well. No severe complication occurred. Three patients received further surgical operations for aesthetic reasons. The movement of the corners of mouth was classified as excellent in 8 cases, good in three cases, and fair in one cases. The static angle and dynamic angle of postoperation improved and the range of dynamic angle improvement was larger than that of static angle. CONCLUSION: Free functional gracilis transfer innervated by the CFNG is an ideal technique for facial paralysis. It can effectively improve the facial dynamic of the affected side.

Serum 25-hydroxyvitamin D is negatively associated with severe periodontitis: a cross-sectional study.

BACKGROUND: Periodontitis can lead to the destruction of periodontium and adversely influence the overall health, wellbeing, and quality of life. However, studies on the relationship between severe periodontitis and serum 25-hydroxyvitamin D [25(OH)D] are limited. This study is designed to explore the relationship between 25(OH)D and severe periodontitis. METHODS: A cross-section study of 2928 participants enrolled from the National Health and Nutrition Examination Survey (NHANES) from 2013 to 2014 was conducted. The periodontal examination was performed using a total oral periodontal examination program, and probe measurements were collected at six sites per tooth in NHANES. Severe periodontitis was characterized as: ≥ 2 interproximal sites with attachment loss (AL) ≥ 6 mm (not on the same tooth) and ≥ 1 interproximal site with probing depth (PD) ≥ 5 mm. Severe periodontitis and serum 25(OH)D were the dependent and independent variables, respectively. Univariate, multivariate, and subgroup analyses were performed to explore the relationship between severe periodontitis and serum 25(OH)D. RESULTS: Among the 2928 participants, the average age of the population was 50 ± 13.71 years old, with 1425 (48.67%) males, 316 (10.79%) exhibited severe periodontitis. Serum 25(OH)D showed a significantly negative association with severe periodontitis after adjusting all variables (OR 0.75, 95% CI 0.63-0.89). In addition, severe periodontitis has a nonlinear relationship with serum 25(OH)D, whoes inflection point was 102 (nmol/L). On the left side of the inflection point (25(OH)D ≤ 102 nmol/L), the effect size was 0.98 and 95%CI was 0.98-0.99 (25(OH)D per 1 nmol/L increments). On the right side of the inflection point (25(OH)D > 102 nmol/L), the effect size was 0.99 and 95% CI was 0.98-1.01. The subgroup analysis showed pronounced changes in non-Hispanic white, alcohol consumption, diabetes, and health insurance. CONCLUSION: Serum 25 (OH) D in relation to severe periodontitis is nonlinear in our study.When serum 25 (OH) D is less than 102 nmol/L, serum 25 (OH) D is negatively associated with severe periodontitis.

Effects of non-surgical periodontal therapy on periodontal clinical data in periodontitis patients with rheumatoid arthritis: a meta-analysis.

BACKGROUNDS: To date, there is still no consensus about the clinical efficacy of non-surgical periodontal therapy in rheumatoid arthritis (RA) patients with periodontitis. Therefore, the aim of this study was to summarize clinical data regarding the efficacy of scaling and root planing (SRP) in patients with RA and periodontitis compared to non-RA periodontitis patients. METHODS: We selected randomized controlled trials (RCTs) that compared periodontal clinical data in RA as compared to non-RA periodontitis patients by searching Embase, PubMed and Cochrane Central Register of Controlled Trials and by manually retrieving from the earliest records to March 8, 2021. The overall effect size of plaque index (PI), gingival index (GI), attachment loss (AL), probing depth (PD) and bleeding on probing (BOP) were calculated by either a fixed or random-effect model, and subgroup analyses were conducted according to the different time points of follow-up. Two investigators extracted the data and assess the accuracy of the obtained results with 95% of Confidence Intervals (CI). Cochrane Collaboration's tool was responsible for the evaluation of the literature quality and the inter-study heterogeneity was evaluated by Q test and I2 statistic. Sensitivity analyses were applied for results with heterogeneity. Publication bias was determined by Begg's test, Egger's test and the trim-and-fill method. RESULTS: Seven RCTs including 212 patients eventually met the inclusion criteria for the study. As the primary results, the change of PD was not statistically significant and in the secondary results changes of PI, GI, AL and BOP were also not statistically significant in RA patients with periodontitis compared to non-RA periodontitis patients. In subgroup analysis, a larger BOP reduction at 3 months, PI and AL reduction at 6 months were observed in patients with RA and periodontitis group. The results of sensitivity analyses had no significant effect. No evidence of potential publication bias was tested. There were some limitations due to the small number of eligible RCTs. CONCLUSIONS: SRP is equally effective in RA as compared to non-RA periodontitis patients. It suggests RA does not affect the clinical efficacy of non-surgical periodontal therapy. These results could serve evidence-based practice.

C6 ceramide motivates the anticancer sensibility induced by PKC412 in preclinical head and neck squamous cell carcinoma models.

The purpose of this study was to evaluate the anti-head and neck squamous cell carcinoma (anti-HNSCC) cell activity by C6 ceramide and multikinase inhibitor PKC412. Experiments were performed on HNSCC cell lines (SQ20B and SCC-9) and primary human oral carcinoma cells. Results showed that PKC412 inhibited HNSCC cell proliferation without provoking apoptosis activation. Cotreatment of C6 ceramide significantly augmented PKC412-induced lethality in HNSCC cells. PKC412 decreased Akt-mammalian target of rapamycin (mTOR) activation in HNSCC cells, facilitated with cotreatment of C6 ceramide. In contrast, exogenous expression of a constitutively active Akt restored Akt-mTOR activation and attenuated lethality by the cotreatment. We propose that Mcl-1 is a primary resistance factor of PKC412. The cytotoxicity of PKC412 in HNSCC cells was potentiated with Mcl-1 short hairpin RNA knockdown, but was attenuated with Mcl-1 overexpression. Intriguingly, C6 ceramide downregulated Mcl-1 in HNSCC cells. In vivo, PKC412 oral administration inhibited SQ20B xenograft tumor growth in severe combined immunodeficient mice. The antitumor activity of PKC412 was further sensitized with coadministration of liposomal C6 ceramide. Together, we suggest that PKC412 could be further studied as a promising anti-HNSCC strategy, alone or in combination with C6 ceramide.

[Analysis of Medication Laws for Chinese Medicine Treating Hypertension Patients with Yin Defi- ciency Yang Hyperactivity Syndrome Based on Literatures].

OBJECTIVE: To analyze medication laws of Chinese medicine (CM) treatment in hypertension patients with yin deficiency yang hyperactivity syndrome. METHODS: China National Knowledge Infrastructure (CNKI, Jan. 1979-Dec 2014), Chinese Scientific Journals Database (VIP, Jan 1989-Dec2014), Chinese Biomedical Literature Database (CBM, Jan.1978-Dec.2014), Wanfang Database (Jan 1990-Dec 2014) were retrieved by using "hypertension", "CM", "Chinese herbs", "syndrome" as keywords. Totally 149 literatures concerning CM treatment for hypertension patients with yin deficiency yanghyperactivity syndrome were included in this study. The herbs database was established by SPSS20.0,and correlation laws were analyzed by SAS9.3. With the Pajek3.1, results were presented visually withcomplex networks. RESULTS: There were 149 literatures including 131 kinds of herbs with 1,598 frequencies. The conventional compatibility program of herbs for asthenic yin and predominant yang syndrome of hypertension were two toothed achyranthes root, tall gastrodia rhizome, Cassia obtusifolia L., eucommiabark, baikal skullcap root, and so on, about 29 kinds. Of them, core herbs were two toothed achyranthes root, tall gastrodia rhizome, Cassia obtusifolia L., poria, prepared rhizome of rehmannia, oriental water-plantain tuber, asiatic cornelian cherry fruit, Uncariae Rhynchophylla, common yam rhizome, the rootbark of the peony tree, and so on. CONCLUSION: Medication laws of CM treatment in hypertension patientswith yin deficiency yang hyperactivity syndrome obtained by analysis of complex networks reflected thetherapeutics of nourishing yin to suppress yang, which could further provide reference for clinical studies.

Highly Sensitive CO2-Responsive Polymeric Microgels That Respond Within Seconds.

In this work, polymeric microgels with swift response to CO2 are synthesized by polymerization of tertiary-amine containing methacrylate monomers (N,N-diethylaminoethyl methacrylate, DEAEMA) and polyethylene glycol monomethyl ether acrylate (PEGMA) as stabilizers. The obtained microgels are stable but very sensitive to CO2, which can rapidly swell and further collapse within 5 s upon bubbling of CO2, or within minutes in an atmosphere of gaseous CO2. The protonation of the tertiary amine groups in the presence of CO2 induces sensitive swelling and further irreversible collapse of the microgels due to the internal charge repulsion and relatively low cross-linking density in the core area of microgels. This rapid response to CO2 may find further applications in the fields of sensitive detection or responsive loading and release upon CO2 stimulus.

Characterization and Pharmacokinetic Study of Aprepitant Solid Dispersions with Soluplus®.

Solid dispersions are a useful approach to improve the dissolution rate and bioavailability of poorly water-soluble active pharmaceutical ingredients (APIs). The aim of this study was to improve the physicochemical properties and bioavailability of a poorly water-soluble aprepitant by preparation of solid dispersions. The solid dispersions were characterized by dissolution, FTIR, XRPD, DSC, SEM and pharmacokinetic studies in rats. The dissolution rate of the aprepitant was significantly increased by solid dispersions, and XRD, DSC, and SEM analysis indicated that the aprepitant existed in an amorphous form within the solid dispersions. The result of dissolution study showed that the dissolution rate of SDs was nearly five-fold faster than aprepitant. FTIR spectrometry suggested the presence of intermolecular hydrogen bonds between the aprepitant and polymer. Pharmacokinetic studies in rats indicated that the degree drug absorption was comparable with that of Emend®. Aprepitant exists in an amorphous state in solid dispersions and the solid dispersions can markedly improve the dissolution and oral bioavailability of the aprepitant. The AUC0-t of the SDs was 2.4-fold that of the aprepitant. In addition, the method and its associated techniques are very easy to carry out.

High deposition and precise stimulus-response release performance of lignin-coated dendritic mesoporous organosilica nanoparticles for efficient pesticide utilization.

The inefficient and improper use of conventional pesticides has prompted the development of targeted and cost-effective pesticide delivery systems, which aim to optimize the efficient utilization of pesticides while minimizing environmental pollution in surrounding areas. In this paper, a dual-stimuli-responsive pesticide slow-release nanopesticide system (NES@DMONs@LGN) was designed in this study, utilizing mesoporous silica (DMONs) as a nanocarrier and lignin (LGN) as a capping agent to encapsulate the pesticide molecules within DMONs. This system enables intelligent release of pesticide molecules while preventing environmental pollution caused by leakage. Additionally, NES@DMONs@LGN exhibit excellent specific loading efficiency. The abundant hydrophilic functional groups in the lignin layer on the surface of NES@DMONs@LGN can establish hydrogen bonds with advanced fatty acids and fatty alcohols present in the waxy epidermis of plants, thereby significantly enhancing carrier wettability and adhesion. Typically, phytophagous lepidopteran pests have an alkaline midgut and possess lignin-degrading enzymes. The NES@DMONs@LGN developed in this study are capable of rapid release under high temperature and alkaline conditions. Therefore, the precise release of pesticide molecules in the target pests can be achieved, thus increasing the actual utilization rate of pesticides. The experimental results demonstrated that NES@DMONs@LGN effectively prevented photodegradation of the active ingredient after 48 h of UV irradiation, resulting in a 3.7-fold improvement in photostability and providing robust UV protection. By encapsulating pesticide molecules with nanocarriers, the release of pesticides in non-targeted environments can be prevented, thereby significantly reducing toxicity to zebrafish. Thus, this study provides a promising solution for sustainable greening of agriculture.

Advances in the Design of Functional Cellulose Based Nanopesticide Delivery Systems.

The advancement of science and technology, coupled with the growing environmental consciousness among individuals, has led to a shift in pesticide development from traditional methods characterized by inefficiency and misuse toward a more sustainable and eco-friendly approach. Cellulose, as the most abundant natural renewable resource, has opened up a new avenue in the field of biobased drug carriers by developing cellulose-based drug delivery systems. These systems offer unique advantages in terms of deposition rate enhancement, modification facilitation, and environmental impact reduction when designing nanopesticides. Consequently, their application in the field of nanoscale pesticides has gained widespread recognition. The present study provides a comprehensive review of cellulose modification methods, carrier types for cellulose-based nanopesticides delivery systems (CPDS), and various stimulus-response factors influencing pesticide release. Additionally, the main challenges in the design and application of CPDS are summarized, highlighting the immense potential of cellulose-based materials in the field of nanopesticides.

Human adipose-derived stem cells can optimize the filling material in rats.

BACKGROUND: Human adipose-derived stem cells have been identified as a promising candidate for cell-assisted therapy to improve graft survival. OBJECTIVE: To objective of the study was to add human adipose-derived stem cells into filling materials. METHODS: The filling materials were prepared and divided into 6 groups: fat particles with phosphate buffer saline or human adipose-derived stem cells; acellular dermal matrix particles with phosphate buffer saline or human adipose-derived stem cells; mixture of fat particles and acellular dermal matrix particles with phosphate buffer saline or human adipose-derived stem cells. The survival rate, vascular density and histological at 2, 6 and 12 weeks were investigated. RESULTS: Human adipose-derived stem cells significantly improved survival rate in each group at 6 and 12 weeks, and it significantly increased the vascular density in the fat particles and porcine acellular dermal matrix combined group and porcine acellular dermal matrix group at three time points, but human adipose-derived stem cells did not have a significant effect in the fat particles group. CONCLUSION: Human adipose-derived stem cells as assisted cells added into filling material can improve survival rate and vascular density in rats.

Complete bio-degradation of poly(butylene adipate-co-terephthalate) via engineered cutinases.

Poly(butylene adipate-co-terephthalate) (PBAT), a polyester made of terephthalic acid (TPA), 1,4-butanediol, and adipic acid, is extensively utilized in plastic production and has accumulated globally as environmental waste. Biodegradation is an attractive strategy to manage PBAT, but an effective PBAT-degrading enzyme is required. Here, we demonstrate that cutinases are highly potent enzymes that can completely decompose PBAT films in 48 h. We further show that the engineered cutinases, by applying a double mutation strategy to render a more flexible substrate-binding pocket exhibit higher decomposition rates. Notably, these variants produce TPA as a major end-product, which is beneficial feature for the future recycling economy. The crystal structures of wild type and double mutation of a cutinase from Thermobifida fusca in complex with a substrate analogue are also solved, elucidating their substrate-binding modes. These structural and biochemical analyses enable us to propose the mechanism of cutinase-mediated PBAT degradation.